You will receive a solid 'Old English' brass lock, approximately 8 cm in diameter and weighing 180 grams, with a strong steel shackle. A masterpiece of a padlock—and it's specially prepared.
No one can open the lock without the key.
Except for you! It doesn't take a second. A subtle movement of a fingernail and voila—the lock is open.

This results in a multitude of trick possibilities: Of course, all kinds of escape illusions, but also completely different effects, such as this one:

A spectator closes the lock and inserts the key. They immediately place the lock in a bag or box and hand it back to the spectator, who then waves a piece of paper bearing the name Houdini (or rather, appears) over it. If they take the lock out again, it has opened—thanks to the "magic of Houdini"!